Abstract
The worlds medium and heavy duty diesel vehicle fleets consist of over 20 million vehicles with over 2 million new vehicles added each year. These vehicles are energy efficient, but suffer emissions problems for which solutions are being found.
Natural gas used in a diesel cycle engine, will also allow efficient operation with added benefits of lower regulated and unregulated emissions, lower Greenhouse gas (GHG) emissions, and good economics. With potential shortages of crude oil and plentiful natural gas, the diesel engine has the potential to emerge as a natural gas engine with all of the diesel engines well known attributes.